The present invention relates to an automatic door operating mechanism. More particularly, the present invention relates to an automatic door that is responsive to a control system even during a power outage situation. Specifically, the present invention relates to a hydraulic control system normally responsive to electrical control signals, but also having a safety feature for achieving a closed or open condition of an automatically operated door even during a power outage situation.
An automatic door mechanism is commonly integrated with other elements all to form a system to accomplish a prescribed end purpose; e.g., an elevator control system responsive to the needs of conveying passengers, or a door control system that is responsive to the needs of the handicapped allowing ingress or egress to and from a room or building.
An elevator control system provides for the automatic stopping of an elevator at a level which is even with the floor opening of door. The elevator control system provides various safety functions; for example, causing the automatic reopening of a closing door when a passenger steps into the elevator car so as to avoid undesired contact therebetween. These safety functions are well known and performed by conventional electrical control systems.
A door control system that accommodates the needs of the handicapped shares some of the concerns of the elevator control system; for example, the opening or re-opening of a door in response to a depression of a push button or to a signal generated by motion or object detecting devices, or the like. Although the control systems that provide for automatic functions, as well as the safety functions, serve well their desired needs, these control systems suffer from the drawbacks sometimes occurring upon the loss of power which de-energizes the associated control system rendering it inoperative. It is desired that an automatic control system for operating a door be provided having safety means that function so that the opening or closing of a door may be accomplished, even in the presence of a power outage situation.